Heat Generation Method and Device Using Ionic Vacancies Generated by Electrochemical Reaction

ABSTRACT

The present invention provides: a heat generation method that makes the first use of the ionic vacancies that are a by-product of an electrochemical reaction and have conventionally been left unreacted; and a device for implementing the same. The present invention pertains to: a heat generation method characterized by comprising colliding, in an electrochemical reaction that proceeds in an electrolysis cell, ionic vacancies having a positive charge generated at an anode and ionic vacancies having a negative charge generated at a cathode; and a heat generation device characterized by being equipped with an electrolysis cell provided with an anode and a cathode and an electrolyte solution accommodated within the electrolysis cell, and by generating heat by colliding ionic vacancies of opposite signs generated by causing the electrochemical reaction to proceed in the electrolysis cell via the anode and the cathode.

TECHNICAL FIELD

The present invention relates to a device (equipment) of heat generation(heat production) utilizing the reaction heat of ionic vacancies createdin electrochemical reactions. In more detail, the present inventionespecially relates to a method and a device enhancing the efficiency ofheat production by increasing the mixing effect of a solution containingionic vacancies created at a cathode and an anode. The method and deviceof this invention have made further possible highly efficient recoveryetc. of the reaction heat generated and accumulated during recirculationof solution.

BACKGROUND ART

As electricity bill increases, to improve the efficiency of energyutilization, we have been confronting an important problem, i.e., theeffective utilization of the wasted heats in electrolysis industry suchas copper refinement and water electrolysis, and the development ofredox battery for load leveling. These wasted heats involve theelectricity consumption arising from the electrolytic current flowing inthe reactions at the cathode and anode, or Joule's heat from theelectricity consumption when charging and discharging and the reactionheats in electrochemical reactions (i.e., electrolysis and batteryreaction). Especially, in electrolysis industry, the recovered wastedheats are utilized for heating of raw materials and heat-retention ofelectrolysis cells, contributing to reduction of manufacturing cost(e.g., non-patent document 1).

On the other hand, it is well known that voids with positive andnegative charges (ionic vacancies) exist in solid crystals. Ionicvacancy generally implies a defect structure occurring in solidcrystals, of which actual situation is interpreted as an atomic-scalevoid with electric charges resulting from the disorder of thearrangement of a crystal. It has never been thought that ionic vacanciesexist in liquid solutions. However, in recent years, inmagnetoelectrochemistry, where electrochemical reactions proceed undermagnetic fields, not always experimentally it has been ascertained thatmicrobubbles originated by ionic vacancies occur (non-patent documents2-4), but also theoretically it has been clarified that to conserve thelinear momentum and electric charge during an electron transfer in anelectrochemical reaction, ionic vacancies are created in liquidsolutions (non-patent document 5),

As schematically shown in FIG. 1 , the structure of ionic vacancy 1 inliquid solution is composed of a free space part 2 (free space core)with a diameter of order of 0.1 nm surrounded by outer shell 3 ofsolvent molecules which are polarized by different sign depending on acathodic or anodic reaction (in FIG. 1 , due to cathodic reaction, minussigns are taken.). Furthermore, the outer shell is thought to be coveredwith an ionic cloud 4 with opposite charges. The lifetime wasexperimentally determined about 1 second (non-patent document 2).

The chemical and physical natures of ionic vacancy are similar to thoseof hydrogen ion: Instead of hydrogen molecules arising from hydrogenions, nanobubbles from ionic vacancies can promote dendritic growth ofdeposit metal (Magnetodendrite effect) (non-patent document 6). Althoughionic vacancies with the same sign electrically repel each other, theycan collide to be united, yielding nanobubbles (non-patent document 7).Moreover, other phenomena have been also known, e.g., from furtherunions by the collisions of nanobubbles, microbubbles are formed, whichcan be observed with an optical microscope, etc.

As mentioned above, though the interesting natures and behaviors ofionic vacancies are being clarified, there is no example applying themto industrial fields. For example, since the usual devices of heatrecovery mentioned above have no mechanism to utilize ionic vacancies,the collectable heat energies were limited to Joule's heat and thereaction heats of electrochemical reactions (e.g., patent documents 1and 2).

CITATION LIST Patent Documents

-   Patent document 1: Japanese Unexamined Patent Application    Publication No. 2020-216705.-   Patent document 2: Japanese Unexamined Patent Application    Publication No. 2017-050418.

Non-Patent Documents

-   Non-patent document 1: H. Ikeuchi, et al, Light Metal, vol. 30, No.    2, p. 111 (1980).-   Non-patent document 2: A. Sugiyama, et al, Sci. Rep., 6, 19795    (2016).-   Non-patent document 3: M. Miura, et al. Electrochemistry, 82, 654    (2014).-   Non-patent document 4: Y. Oshikiri, et al, Electrochemistry, 83, 549    (2015).-   Non-patent document 5: R. Aogaki, et al. Sci. Rep., 6, 28927 (2016).-   Non-patent document 6: M. Miura, et al, Sci. Rep., 7, 45511 (2017).-   Non-patent document 7: R. Aogaki, et al, ECS Transaction, 16, 181    (2009).

SUMMARY OF THE INVENTION Problems to be Solved by the Invention

By examining the behaviors of ionic vacancy in liquid solutions more indetail, the present invention first provides the industrial utilizationof ionic vacancy.

Means for Solving the Problems

Devoting themselves to study the behaviors of ionic vacancies in liquidsolutions, the present inventors have first found the phenomenon of heatproduction (heat generation) by the collision between ionic vacancieswith opposite charges, and then completed the present invention.

Namely, this invention provides a method of heat production comprising:making collisions between an ionic vacancy with positive charge createdat an anode and an ionic vacancy with negative charge created at acathode in an electrochemical reaction which proceeds within anelectrolysis cell, and a device of heat production to perform themethod.

Advantageous Effects of the Invention

By means of the heat production method and device of this invention, theenergy holders inherent in electrolytic solutions, i.e., ionicvacancies, which are in vain abandoned in usual recovery of heat, can beutilized as a heat source based on the new principle.

In the present invention, only by colliding with each other of ionicvacancy with different sign produced in every electrochemical reaction,heat production is effectively obtained. Since every electrochemicalreaction can be used without any restrictions, and it is practicable bysimple and easy ways such as streaming electrolytic solution, thisinvention can be applied to all kinds of industries usingelectrochemical reactions.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 A schematic of an ionic vacancy with negative charges in a liquidsolution.

FIG. 2 A schematic exhibiting the structure of an example (driving anelectrolytic solution by a Lorentz force) for the device of heatproduction (device of reaction heat generation) by this invention.

FIG. 3 The schematics of other examples of the device by this invention,where an electrolytic solution is drived by a Lorentz force.

FIG. 4 The schematic of an example of the device by this invention,where an electrolytic solution is drived by a circulation pump.

FIG. 5 The schematic of an example of the variation in electrode part,where multiple plane electrodes are used.

FIG. 6 The schematics of the examples of the variation in the electrodepart, where (A) Mesh-type electrodes and (B) Sintered porous electrodesare used.

FIG. 7 The schematics of the examples of the variation in the device ofthe present invention. (A) The example equipped with the recovery meansof heat composed of extended channels; (B) The example equipped withmultiple parallel plates for the means of heat recovery.

FIG. 8 The schematics of the examples of variation in the device by thisinvention. (A) The example equipped with meandering tubular means ofheat recovery. (B) The example equipped with spiral means of heatrecovery.

FIG. 9 The schematic of an example of variation (narrowing the intervalof electrodes).

FIG. 10 The schematics of the examples of the variation in the deviceshown in FIG. 9 . (A) The example of layered electrodes; (B) The exampleof flexible electrodes; (C) The example of rolled flexible electrodes.

FIG. 11 The schematic of an example of the device of the heat productionby this invention, which is fabricated by the microprocessing usingphoto-lithography.

FIG. 12 The photo of the electrolysis cell used in Example 1, which wasproduced experimentally (A), and the schematic cross section showing thestructure of it (B).

FIG. 13 The photos of the interior of the electrolysis cell used inExample 1. (A) Before electrolysis, (B) During electrolysis.

FIG. 14 The graph of the temperature change against electrolytic currentat an external magnetic field of 10 T, which was performed by theexperimentally produced apparatus in Example 1. (a) Solid line shows thetemperature change (K) of the electrolytic solution, (b) Break lineshows the temperature change by Joule's heat.

FIG. 15 The graph of the produced heat against magnetic flux density inExample 1.

FIG. 16 The schematic of the rough sketch of the experimentally producedapparatus with three-layered electrodes used in Example 2.

FIG. 17 The graph of the relationship between the produced excess heatand the electrode structure measured in Example 2.

MODES FOR CARRYING OUT THE INVENTION

In the following, the present invention is explained in detail.

FIG. 1 shows the schematic expressing an ionic vacancy with negativecharges created near the cathode and a positive ionic cloude surroundingit (from now on called ‘minus ionic vacancy’). Near the anode, ionicvacancy with opposite (positive) charges (from now on called ‘plus ionicvacancy’) is created. A plus ionic vacancy is thought to take astructure reversing the charges shown in FIG. 1 .

The inventors have experimentally validated the heat production inaccordance with the following mechanism; when a pair of minus and plusionic vacancies collide with each other, the electric charges of bothionic vacancies are neutralized, leading to annihilation. At the sametime, their dynamic energies for vacancy formation are emitted as heatto solution phase, producing heat.

The heat production method of this invention is the method utilizing themechanism mentioned above, i.e., the heat production method utilizingthe heat produced by the collision between plus and minus ionicvacancies in a liquid solution (electrolytic solution).

Although accompanied with electrochemical reactions such aselectrolysis, ionic vacancies are created near the electrodes, no onehave known the existance in liquid solutions, resultantly consideringthe utilization before. In addition, since in the large-sizedelectrolysis cells using metallic refinement and water electrolysis, thecathode and anode are installed far away, in view of a ca. 1 secondlifetime of ionic vacancy, the possibility of the collision betweenminus and plus ionic vacancies is almost zero. As a result, in theordinary systems of electrolysis devices, the heat originated by ionicvacancies has not been accidentally utilized.

The heat production method of this invention contains the collisionsbetween ionic vacancies with positive electric charges created at anode(plus ionic vacancies) and ionic vacancies with negative electriccharges created at cathode (minus ionic vacancies).

In this specifications, the word ‘collide’ implies to make an approachbetween ionic vacancies as near as they can interact with each other.Since plus and minus ionic vacancies have opposite electric charges,approaching each other as near as electrostatic attractive force works,they collide to make annihilation accompanied by heat production.

For example, in copper redox reaction, ionic vacancies with plus andminus two-unit charges are created in accordance with the followingequations.

C_(u) ²⁺+2e ⁻→Cu+V²⁻(cathodic reaction)  (1)

C_(u)−2e ⁻→Cu²⁺+V₂₊(anodic reaction)  (2)

-   -   (V²⁻ and V₂₊ denote ionic vacancies with minus and plus two-unit        charges.)

On the other hand, ionic vacancies with a plus and minus single-unitcharge created in the redox reaction of ferricyanide/ferrocyanide ionsare created in the following equations.

[Fe(CN)₆]³⁻ +e ⁻→[Fe(CN)₆]⁴⁻+V⁻(cathodic reaction)  (1′)

[Fe(CN)₆]⁴⁻ −e ⁻→[Fe(CN)₆]³⁻+V₊(anodic reaction)  (2′)

-   -   (V⁻ and V₊ denote ionic vacancies with minus and plus        single-unit charge.)

Then, plus and minus ionic vacancies with n-unit charges collide witheach other yielding excess heat after a pair annihilation (the followingequation (3)).

V_(n+)+V_(n−)→Null+γ_(col)Q_(ann)  (3)

-   -   (V_(n−) and V_(n+) are ionic vacancies with minus and plus        n-unit charges, γ_(col) is the collision efficiency and Q_(ann)        is the molar excess heat, of which value is equal to the        solvation energy.)

As a result, when the method of this invention is performed, thefollowing two points are important for increasing the obtained heatamount; to improve the collision efficiency of ionic vacancies and/or toincrease the numbers of ionic vacancies created in electrode reactions.Moreover, the heat production also increases with solvation energy takenby ionic vacancy. The possible ways to increase the solvation energy areas follows; (1) electrolyte complex salt containing ions as much aspossible is used as a supporting electrolyte, (2) the concentration ofsupporting electrolyte is heightened, etc., or the following way is alsopossible; to improve the efficiency of heat exchanger through increasingboiling point of solvent by heightening pressure.

To improve the collision efficiency, the following ways are cited; (i)to mix minus ionic vacancies near cathode with plus ionic vacancies nearanode by streaming a solution (electrolytic solution), or (ii) todecrease the distance (interval) between anode and cathode, and soforth.

In the method for mixing (i) mentioned above, as for the driving forceto stream electrolytic solution, for example, we can cite Lorentz forceor mechanical (dynamic) pressure, etc. However, the driving force cannotbe limited by them.

In the case where Lorentz force is used for the driving force, forexample, we can use the magnetohydrodynamic (MHD) electrode (see R.Aogaki, et al, DENKI KAGAKU, 44 (2) 89 (1976)). When adopting mechanical(dynamic) pressure as a driving force, for example, we can force tostream an electrolytic solution by a pump and so forth connected to theelectrolytic cell.

Furthermore, it is desirable that the stream of an electrolytic solutionby the driving forces mentioned above contains a turbulent flow, wherethe turbulent flow is a flow, of which components randomly change withspace and time, containing vortices with various orders of magnitude.

In the heat production method of this invention, under various ideas, wecan make turbulence of an electrolytic solution. For example, afterstreaming an electrolytic solution in a direction given by the drivingforce mentioned above, by applying various devices to the flow channelsof an electrolytic solution (the shape of electrolysis cell, etc.), wecan make a turbulent flow in the electrolytic solution. We can exemplifysome of them as follows; to make turbulence by colliding of anelectrolytic solution against the wall surface of a bending and twistingchannel, to make turbulence at narrowed or expanded portion of a flowchannel with changing cross section (i.e., changing the diameter of thechannel), and to make turbulence by installing mesh-type materials inthe channel of electrolytic solution, and so forth.

The method mentioned above, i.e., (ii) to decrease the distance(interval) between an anode and a cathode can be performed by simplynarrowing the distance between electrodes. Due to the narrowed electrodedistance, ionic vacancies with opposite charges created at the anode andcathode collide with each other by their own molecular motions, so thatsuch a forced flow of an electrolytic solution as mentioned in (i) isnot always necessary. This is because ionic vacancies with oppositecharges exist near an anode and a cathode. However, it is permitted toperform at the same time (ii) decrease of the distance betweenelectrodes, and (i) forced flow of an electrolytic solution.

In (ii), the distance between electrodes is not especially specified aslong as ionic vacancies with opposite signs collide with each other bytheir molecular motions. However, it is desirable to be less than 10 mm,more desirable to be less than 1 mm, and further more desirable to beless than 0.1 mm. For example, we can set up the electrode distancebetween an anode and a cathode, e.g., less than 100 μm, less than 80 μm,less than 60 μm, less than 50 μm, and less than 40 μm, or less thanthese values. Although the lower limit of the electrode distance is notespecially limited as long as at the distance, electrode reactionsproperly proceed, it is normally more than 5 μm or more than 10 nm.

In the situation where the collision frequency of ionic vacancyincreases by (ii) the narrowness of electrode distance, since the flowof an electrolytic solution is not necessary, we can use a paste-type orsolid-type electrolytic solution, so that we can substantially make awhole electrolysis system solidified.

The electrolysis cell having a micrometer order of distance, forexample, can be produced by means of the microfabrication techniqueusing photo-lithography.

As for the method to increase the number of ionic vacancies, we can citethe following examples: (I) to increase the amount of ionic vacanciescreated at an electrode by enlarging electrode area, (II) to increasethe amount of ionic vacancies by increasing ionic concentrationsconcerning electrochemical reactions in a solution, and (III) toincrease the volume of the collision field of minus and plus ionicvacancies created, etc.

(I) and (II) mentioned above are the methods to increase the absoluteamounts of ionic vacancies created, so that they can be combined witheither or both of (i) the forced flow of an electrolytic solution, and(ii) the narrowness of the electrode distance mentioned above. Asmentioned above, (III) is the way preparing the place accommodating theionic vacancies quickly sent after creation, and promoting thecollisions of the ionic vacancies by enlarging the volume of the place,so that it is desirable to be combined with (i) the forced flow of anelectrolytic solution mentioned above.

Namely, the heat production method of this invention indispensablycontains the collisions between the ionic vacancies with negativecharges created at cathodes and ionic vacancies with positive chargescreated at anodes in electrochemical reactions proceeding withinelectrolysis cells, so that it is desirable to further contain theprocesses mentioned above for enhancing the collision frequency of ionicvacancies ((i) or (ii) mentioned above, etc.). In accordance with thecontents, the process to enhance the collision frequency is carried outbefore starting electrochemical reactions (design and production ofelectrolysis cells), or carried out during electrochemical reactions(application of the external forces to electrolytic solutions), orcarried out at the same time.

This invention also provides the devices of heat production to performthe heat production methods.

The devices of heat production of this invention are provided byelectrolysis cells equipped with anodes and cathodes and electrolyticsolutions accommodated in the cells concerned. The anodes and cathodesmentioned above are connected with external power sources, which supplythe electrodes (anodes and cathodes) with electricity to proceedelectrochemical reactions within the electrolysis cells. The devices ofheat production of the present invention furthermore provide the meansto enhance the collision frequency of ionic vacancies created at anodesand cathodes.

As the means to enhance the collision frequency of ionic vacancies, whenforcibly streaming electrolytic solutions, it is desirable that thedevices of heat production of this invention are moreover provided withthe driving means of electrolytic solutions which prepare the drivingforce to move electrolytic solutions and the mixing means ofelectrolytic solutions which prepares the mixing spaces of minus andplus ionic vacancies. As driving means of electrolytic solutions, we canexemplify magnetohydrodynamic (MHD) electrodes and pumps to circulateelectrolytic solutions by mechanical (dynamic) pressures and so forth.It is preferable for the driving means of electrolytic solutions tocontain the means to make turbulence in the flows of the electrolyticsolutions. As the means to make turbulence, we can exemplify bendingflow channels, channels with decreasing and/or increasing diameters,materials installed within channels to disturbe the flows ofelectrolytic solutions (diffusers of mesh-type materials etc.).

It is more preferable that the devices of heat production of thisinvention are furthermore equipped with some heat recovery means of theheat arising from the collisions of ionic vacancies within electrolysiscells (heat-exchange unit, etc.).

We shall explain the devices of heat production of the present inventionconcerning some concrete examples. However, the present invention is notlimited by these concrete examples. As long as the technical philosophyof this invention is embodied to utilize the heat production by thecollision between minus ionic vacancies and plus ionic vacancies, thedevices optionally modifying and changing the concrete examples statedin the following are also involved in this invention.

FIG. 2 shows an example of the device of heat production utilizing anelectromagnetic force (Lorentz force) as the means of driving anelectrolytic solution. This device of heat production 5 containselectrolytic solution 58 in electrolysis cell 10 with cathode 6 andanode 7, proceeding electrochemical reactions by applying voltage from apower source (not illustrated) to cathode 6 and anode 7. The device inFIG. 2 is also installed by an device generating a magnetic field in thedirection from the back side to the front side of FIG. 2 . By imposingthe magnetic field to electrolysis cell 10, in the direction of arrow 8(from the left to the right in FIG. 2 ), a Lorentz force occurs, so thatthe electrolytic solution moves (flows). Accompanied with the flow ofthe electrolytic solution, ionic vacancies 9 also transfer. In theturbulence occurring near the inner wall of electrolysis cell 10 (thecurved portion of the flow channel: the means enhancing the collisionfrequency), minus ionic vacancies and plus ionic vacancies collide andreact in high frequency, producing heat.

FIG. 3 represents a modified example of the device of heat productionutilizing an electromagnetic force (Lorentz force). In this example, asan electrode working under an external magnetic field B, an electrodecalled the deviation-type of cyclotron MHD electrode (see M. Miura, etal Sci. Rep., 7, 45511 (2017)) is used, where the configuration ofelectrodes is changed. As shown in FIG. 3(A), the MHD electrode iscomposed of two cylinder-type electrodes (14 and 15) with differentdiameters; inner electrode 14 is inserted in the inside of outerelectrode 15. The outer wall of outer electrode 15 is insulated, whereasthe inner wall works as an electrode surface for one part (anodic orcathodic) of an electrochemical reaction. On the other hand, the outersurface of inner electrode 14 works as an electrode surface for anotherpart (cathodic or anodic) of the electrochemical reaction. In thedeviation-type cyclotron MHD electrode shown in FIG. 3 , the centralaxis of inner electrode 14 is placed deviated from the central axis ofouter electrode 15 (On the contrary, in the ordinary cyclotronelectrode, the central axes are set in the same place). The gap betweenboth electrodes is filled with electrolytic solution 58.

As shown in the cross section in FIG. 3 (B), under an external magneticfield B (oriented from the back side to front side of this paper), by anelectrolysis current flowing between electrodes 14 and 15, anelectrolytic solution flows by the Lorentz force around inner electrode14, circulating in anticlockwise direction 8. After the electrolyticsolution passes through the narrow part between both electrodes 14 and15 (the left side of electrode 14 in FIG. 3 (B): the means to enhancecollision frequency), a turbulent flow occurs, yielding the reactionheat of ionic vacancies. This is because ionic vacancies are denselymixed, colliding with each other in high frequency.

As shown in FIGS. 2 and 3 , in the device of heat production using theLorentz force as a driving force of the electrolytic solution, it isdesirable that the external magnetic field is strong as much aspossible. In the present invention, the magnetic flux density of theexternal magnetic field is desirable to be more than 0.01 T (Tesla),more desirable to be more than 0.1 T, and the most desirable to be morethan 0.5 T. Under 0.01 T, we can not always expect the sufficient mixingeffect. We can use various magnetic fields which are not always uniform,but also non-uniform in position and time. Putting some ferromagneticsubstances in a magnetic field, we can add non-uniformity to theexternal magnetic field, or make the magnetic field strengthened.

FIG. 4 exhibits an example using the apparatus of mechanical circulation(circulation pump P) 21. The apparatus is provided by electrolysis cell10 with two electrode 6 and 7. The electrolysis cell 10 concerned isequipped with two openings, and each opening is connected to thecirculation pump 21 through channel 22. The insides of electrolysis cell10 and channel 22 are filled with electrolytic solution 58.

The device in FIG. 4 performs the following processes: Electrochemicalreactions are proceeded by the voltage applied or the current flowingbetween electrodes 6 and 7, so that ionic vacancies are created. At thesame time, with circulation pump 21, we circulate (stream) electrolyticsolution 58 within the apparatus (e.g., in the direction of arrow 8 inFIG. 4 ), so that the ionic vacancies created at the electrodes alsomove in the direction of arrow 8. Then, the vacancies are mixed witheach other in the turbulence occurring in the neighborhood from theopening 10 of the electrolysis cell to the inlet of channel 22 of anelectrolytic solution (the part of reducing diameter of channel: themeans to enhance the collision frequency), producing heat by thecollision and reaction of ionic vacancies with opposite signes.

In FIG. 2 and FIG. 4 , though the device provided by a pair of planeelectrodes facing each other (anode and cathode) is exemplified, asshown in FIG. 5 , layered multiple electrodes are also permitted. In theexample of FIG. 5 , by applying voltage between a pair of the most outerelectrodes of the layered ones (32 a and 32 e), electrochemicalreactions proceed between the electrodes adjoining via an electrolyticsolution (e.g., between 32 a and 32 b, or 32 b and 32 c, etc.),producing a large amount of ionic vacancies. The ionic vacancies createdat the electrodes move with the flowing electrolytic solution in thedirection of arrow 8 in FIG. 5 . By installing the means of makingturbulence (e.g., mesh-type materials) in the neighborhood of the outletof the electrodes, a large amount of ionic vacancies created collide andreact, producing heat.

In the present invention, the corresponding electrochemical reactionsare not specifically restricted by the kinds, i.e., electrode materials,compositions of electrolytic solutions and electrolysis potentials, etc.It is because as long as containing electron transfer, in anyelectrochemical reactions, ionic vacancies are created. Therefore, it ispossible not always to introduce it to the devices using large-scaleelectrolysis cells (electrolysis vessels) such as in electrolysisrefinement of copper and aluminum, etc., but also to apply it toheat-production devices of which systems are unified and miniaturized(e.g., portable heat-production device). In addition, the size andsolvation energy of ionic vacancy tend to increase with the number ofunit charge, so that from the viewpoint of increasing the collisionfrequency per a pair of ionic vacancy and the heat production by pairannihilation, it may be preferable that we choose electrochemicalreactions creating ionic vacancies with large numbers of unit charges.

FIG. 6 represents other modified examples: FIG. 6 (A) is an exampleusing metal-mesh-type electrodes 27 with grid space, and FIG. 6 (B) isan example using sintered porous electrodes 30. In the electrolysiscells equipped with these electrodes, when an electrolytic solutionflows in the direction vertical to each electrode surface (in thedirection of arrow 8 in FIG. 6 ), turbulence of the solution takes placeby passing through the mesh and porous pores, so that the collisionfrequency of ionic vacancies created at the electrodes is promoted.Namely, in the examples shown in FIGS. 6 (A) and (B), the electrodestructure serves both as a means of creating ionic vacancies and a meansof enhancing collision frequency (the means of making turbulence). Inthese examples, it is also permitted to promote the efficiency of heatproduction by using the electrodes layered with more than one pairelectrodes of mesh-type electrodes 27 and porous electrodes 30. Needlessto say, we can make the shape of electrode not always plane, but alsocurved or cylindrical.

As to the products of electrochemical reactions in an electrolysis cell,we can suppose the following cases; one is the case where there is noproduct in solution except for precipitating impurity slime like incopper electrolysis refinement, and the other is the case where hydrogenand oxygen evolve as products like in water electrolysis. In the casewhere reaction products of gaseous matters evolve, we can settle acollection part of them.

On the other hand, in the case where reactants must be supplied tocontinue electrochemical reactions (the case where reactants areconsumed by electrochemical reactions), to supply the reactants, we caninstall the reactant-supply part in the electrolysis cell.

FIGS. 7 and 8 exemplify the devices provided with the means of heatrecovery. In each example, electrochemical reactions proceed in theelectrolysis cell with a pair of electrodes 34 and 35, and electrolyticsolution flows in the right direction of the FIGS. (in the direction ofarrow 37).

In FIG. 7 (A), the channel of an electrolytic solution is sharplynarrowed at the outlet of the electrolysis cell (the narrowed part ofchannel) 38, then narrowed again after expanded, finally attaining moreexpanded channel 39. As shown in this example, by rapidly expanding andreducing the cross section of the channel, a turbulent flow occurs inthe electrolytic solution, so that we can enhance the collisionfrequency, increasing the efficiency of the heat production. Since theelectrolytic solution containing the heat produced by the collision ofionic vacancies flows into the expanded part of channel 39, we caneffectively take out the heat for use from the expanded part 39 made ofthe materials with high thermal conductivity. Namely, the expanded part39 plays a role of heat recovery means (heat exchanger).

FIG. 7 (B) is an example that in the expanded part of channel 39 shownin FIG. 7(A), multiple plates of high thermal conductivity are arrangedparallel to the channel at optional intervals. Since when the solutionpasses through the plates, the heat created transfers from the solutionto the plates, we can make the heat exchange more effective.

FIG. 8 is the modified examples for the expanded part of channel 39 inFIG. 7 . i.e., one example where the tubular channel of an electrolyticsolution is bent (meandering) (FIG. 8 (A)) and the other example whereit is spiraled (FIG. 8 (B)). In all cases, it is shown that by makingthe tubular channels of the heat recovery means in optional shapes, inkeeping the whole size small, the device can be adapted for varioususes.

FIG. 9 to FIG. 11 exemplify some devices using the narrowness of theinterval of electrodes as the means for enhancing the collisionfrequency of ionic vacancies.

Ionic vacancies created on an electrode surface form a layer of ionicvacancies of order of 1 μm thickness in the electrolytic solution closeto the electrode. Therefore, if the interval between cathode and anodecan be approached to the same order of distance as the thickness ofionic vacancy layer concerned, we can enhance the collision frequency ofionic vacancies without using the means of an electrolytic solution flowmentioned above. Although it is preferable that we brings one electrodeclose to another as near as possible without a short circuit, it ispreferable that we takes the sum of the thicknesses of plus and minusionic vacancy layers (about 2 μm order) as the lower limit. The upperlimit of the electrode interval is permitted as long as the plus ionicvacancy and minus ionic vacancy collide with each other even if theelectrolytic solution does not flow. For example, it is desired todesign it below 10 mm, preferable below 1 mm, and more preferable below0.1 mm.

In the example shown in FIG. 9 , the interval between cathode and anodeis taken less than 0.1 mm (e.g., 50 nm). As a result, proceedingelectrode reactions by applying potential to a pair of plane electrodes6 and 7, due to molecular motions, we can make ionic vacancies 9 creatednear one of the electrodes collide and react with ionic vacancies withopposite charges created near the other electrode, so that we obtain theheat production. For this type of device, it is possible to unify andminiaturize the whole device, for example, by using paste-like orsolid-like electrolyte 50 as an electrolytic solution in electrolysiscell. To protect a short circuit, it is also permitted that a spacer(porous) is inserted between electrodes (plane electron conductors).

FIG. 10 represents some modified examples of the device of heatproduction shown in FIG. 9 . FIG. 10 (A) is an example where pluralplane electron conductors 46 are inserted between a pair of electrodes.FIG. 10 (B) shows a pair of flexible electrodes 47 faced each other atan interval of less than 0.1 mm through an electrolytic solution 50 anda porous space 48. This electrode can be also provided as anelectrolysis condenser-type of scroll rolling up the electrodesthemselves (FIG. 10 (C)). Moreover, we can also jointly use electrodeswith minute unevenness such as meso-pores (pores with diameters of 2 nmto 50 nm).

FIG. 11 exhibits a schematic of an example of the device of heatproduction by this invention produced by the micro-fabricationtechnology using photo-lithography.

For example, after making an insulator film (e.g., silicon nitride film)72 on an electrode 70 with a metallic thin film formed on a siliconsubstrate surface, removing a part of the silicon nitride film mentionedabove by using photo-lithography, we prepare openings 73. On the otherhande, electrode 71 facing the openings is provided by a metallic thinfilm formed on the surface of silicon substrate (the lower surface inFIG. 11 ).

Filling up a liquid-type, paste-type or solid-type electrolyte inopenings 73 mentioned above, and layering two electrodes 70 and 71, wecan produce the device of heat production by this invention.

EXAMPLES

The present invention will be explained in more detail using thefollowing examples. However, the invention is not limited by them.

Example 1

FIG. 12 (A) is the photo of the electrolysis cell of the heat productiondevice experimentally produced as an Example of this invention, and (B)is the cross section of the schematic structure of the deviceexperimentally produced. The electrolysis cell of this Example (FIG. 12(A)) was composed of a pair of plane electrodes faced each other in aninterval of 5 mm (in the FIG., they are indicated by W. E. and C. E.;copper plane electrodes of a 10 mm height, a 20 mm width and a 1 mmthickness, which was embedded in a transparent acrylic acid resin platewith a 22 mm width.) and the rectangular space surrounded by theelectrodes and the surfaces of the walls of acrylic plates (10 mm high,5 mm wide and 22 mm long), which were glued at the upper and lower sidesof the electrodes. The electrolysis cell concerned was put in acylindrical vessel made of acrylic acid resin with a 25 cm insidediameter, which was filled with an electrolytic solution. The leadconnected to each electrode was extended out of the vessel, and able tobe connected with a power source (not illustrated). In addition, areference electrode to measure the electrode potential (shown by R.E, inthe FIG.) was contacted with the electrolytic solution.

The electrolytic solution used in this Example was a mixed solution ofsulfuric acid (0.5 mol/dm³) and copper sulfate (0.3 mol/dm³). ThisExample was performed by a parallel-plane-type MHD electrode, whichdrove the flow of an electrolytic solution by the electromagnetic force(Lorentz force) arising from an electrochemical reaction under anexternal magnetic field B. Streaming of the electrolytic solution byLorentz force promoted the collisions of plus and minus ionic vacancies.

FIG. 13 represents the photos of the inside of the electrolysis cellbefore (A) and when (B) flowing an electrolysis current (0.24 A) underan external magnetic field of 10 T. In FIG. 13 (B), it was ascertainedthat microbubbles occur in the solution moving with a velocity of ca. 10cm/s in a direction vertical to the magnetic field and the electrolyticcurrent (in the direction of the arrow in FIG. 13 ). Since both of theworking electrode (used as a cathode) (W. E.) and the counter electrode(used as an anode) (C. E.) did not attain the hydrogen- andoxygen-evolution potentials, respectively, it was concluded that theobserved microbubbles are originated from ionic vacancies.

FIG. 14 shows a graph of the relationship between the current (A) andthe temperature change of electrolytic solution (K), when the increasingelectrolytic current from zero in a sweeping rate of 0.2 mA/s under anapplied external magnetic field of 10 T (a solid line). The temperaturechange obtained was compensated by the heat escaping from the vessel.For comparison, the temperature change by Joule's heat is also expressedby a break line, which was calculated from the data of the current andthe measured voltage.

In the electrochemical reaction of this Example, since copperdissolution takes place at an anode and copper deposition occurs at acathode, the reaction heat arising from the reactions is zero. Theelectrodes and the outside of the electrolysis cell are connected onlyby leads, so that heat los of the connection is neglected. Namely,except for the collision of ionic vacancies, the heat generated in theelectrolysis cell is only Joule's heat arising from the electrolysiscurrent.

Then, in FIG. 15 , after doing the similar measurement under variousmagnetic flux densities of the external magnetic field, we plotted theheat amount (heat amount generated by the collision of ionic vacancies)obtained by subtracting the heat amount corresponding to the temperaturechange by Joule's heat from the total heat amount corresponding to thetemperature change of electrolytic solution, which was measured in eachmagnetic flux density. The horizontal axis is the magnetic flux densityof the applied magnetic field (T. Tesla), and the vertical axis is theheat amount obtained from the reaction per each one molar ionic vacancyin this device of heat production (kJ/mol).

As shown in FIG. 14 , due to the heat production from the collision ofionic vacancies, the heat experimentally measured greatly surpassed theJoule's heat arising from the same current.

In addition, the heat amount was determined by using the following cubicequation (4). Namely, applying the value measured by a thermometerattached to the side wall of the electrode and the value of theelectrolysis current to the equation (4) describing the temperaturedifference ΔT between the outside world and the electrolytic solution,we first obtained the coefficients A₀, A₁ and A₃, and then determinedthe heat amount.

ΔT=A ₀ +A ₁ I ² +A ₃ I ³  (4)

It has been already proved that the heat amount obtained by this wayexactly describes the heat amount based on the collision of ionicvacancies.

In FIG. 15 , since in the absence of solution flow under zero magneticflux density, the collisions of ionic vacancies do not occur, the heatamount becomes zero at zero magnetic flux density, whereas in the caseof the increasing solution flow with magnetic flux density, the heatamount also increases, approaching a plateau with largely scatteringdata. As shown in FIG. 13 , with increasing magnetic flux density, thecreation of nanobubbles from the collisions of ionic vacancies with thesame signs and the further creation of microbubbles from nanobubbleswere activated, so that the collisions between ionic vacancies withopposite signs were blocked by them. As a result, it was thought thattogether with reaching an upper limit, the measurements are largelyscattered.

However, as shown in FIG. 15 , the average heat obtained at 15 T by thedevice of this Example was ca. 420 kJ/mol, which is 1.5 times largerthan the combustion heat of hydrogen (285.84 kJ/mol). As the largestvalue obtained, the heat reaching 800 kJ/mol was also observed, which isabout three times larger than the combustion heat of hydrogen.

Since the energy of matter activated by magnetic field is, even at 10 T,of order of magnitude of several J/mol, such a magnetic field energydoes not directly contribute to the heat observed in this Example. It istherefore obvious that the heat amount observed in this Example dependson the collision efficiency of ionic vacancies with opposite signs.

Example 2

We compared the following two heat amounts (heat produced by thecollision of ionic vacancies) obtained by different types of electrodes;one was the case using a pair of (two) electrodes shown in the enfordedexample 1 mentioned above (FIG. 12 ), and the other was the case usingthree-layered electrodes shown in FIG. 16 . The experimental conditions(electrode shapes, materials, electrolysis conditions, etc.) and themeasurement method were the same as the Example 1. In addition, the heatamounts obtained at 10 T in the experiments were averaged, representedin the graph of FIG. 17 .

Since in the case using a three-layered electrode (FIG. 16 (A)), theelectrode areas are twice as much as those of a pair of electrodes, itis theoretically thought that the expected heat amount would be twicelarger than that of two electrodes (a pair electrodes) shown in FIG. 12. However, the heat amount actually measured did not reach the twicevalue of the heat production by a pair of electrodes (ca. 420 kJ/mol)(compared between (1) a pair of electrodes and (2) layered electrodes inFIG. 17 ). However, we performed again the measurement after installingmesh materials (net with 3 mm openings and 0.2 mm diameter fibers) atthe outlet of the electrolytic solution of the layered electrode (FIG.16 (B)), so that we obtained the heat amount twice as much as that of apair of electrodes ((3) layered electrode+net in FIG. 17 ). Namely, byusing the means to enhance the collision efficiency (mesh materials),due to the occurrence of a turbulent flow (Kármán vortex), we could makethe collision efficiency increased, and the heat production efficiencyalso promoted.

INDUSTRIAL APPLICABILITIES

The present invention is composed of the methods of heat production andthe devices of heat production, which first utilize ionic vacancies inelectrolytic solutions never utilized before. The methods and devices ofthe invention are easily applicable to the industries usingelectrochemical reactions operating as before, and we can obtaininexpensive and effective heat production. Furthermore, by miniaturizethe devices of this invention, we can provide small-sized devices ofheat production, which are applicable to potable or other various uses.

EXPLANATION OF SYMBOLS

-   -   1, Schematic diagram of a minus ionic vacancy; 2, Free-space        portion of ionic vacancy (free-space core); 3, Outer shell with        the charges of ionic vacancy; 4, Ionic cloud with opposite        charges; 5, Device of heat production; 6 and 7, Plane electrode;        8. Flow direction; 9, Ionic vacancy; 10, Electrolysis cell        (vessel); 14 and 15, Cylindrical electrode; 21, Apparatus of        mechanical circulation (circulation pump); 22, Channel of        electrolytic solution; 27, Mesh electrode; 30, Sintered or        porous electrode; 32 a to 32 e, Electrode; 34 and 35, Electrode;        36, Electrolysis cell; 37, Flow direction; 38, Reduced part of        channel; 39, Expanded part of channel; 41, Layered parallel        plates; 43, Meandering channel; 45, Spiral channel; 46, Plane        electron conductor; 47, Flexible electrode; 48, Spacer for the        prevention of the short circuit of electrodes; 50, Electrolyte;        58, Electrolytic solution; 61, Microbubble, 62, Current; 63,        Turbulent flow; 64, Middle plane electrode; 65, Mesh materials        (net), 66, Kármán vortex, 70 and 71, Electrode; 72, Insulator        film; 73, Opening.

1.-11. (canceled)
 12. A method of heat production comprising: a step ofmaking collisions between an ionic vacancy with positive charge createdat an anode and an ionic vacancy with negative charge created at acathode in an electrochemical reaction which proceeds within anelectrolysis cell having an electrolytic solution, an anode and acathode; and a step of recovering said heat generated by said collisionsbetween said ionic vacancy with positive charge and said ionic vacancywith negative charge.
 13. The method according to claim 12, furthercomprising a step of enhancing the collision frequency between saidionic vacancy with positive charge and said ionic vacancy with negativecharge.
 14. The method according to claim 13, wherein said step ofenhance the collision frequency comprises driving electrolytic solutionsforcibly streaming.
 15. The method according to claim 14, wherein saidstep of enhance the collision frequency comprises making electrolyticsolutions stream by electromagnetic force arising from applied voltage.16. The method according to claim 15, wherein said electromagnetic forcearises by a device generating a magnetic field installed in saidelectrolytic cell.
 17. The method according to claim 14, wherein saidstep of enhance the collision frequency comprises making electrolyticsolutions stream by applying dynamic pressures.